<?php
/**
 * CGoogleApi class file.
 *
 * @author Qiang Xue <qiang.xue@gmail.com>
 * @link http://www.yiiframework.com/
 * @copyright 2008-2013 Yii Software LLC
 * @license http://www.yiiframework.com/license/
 */

/**
 * CGoogleApi provides helper methods to easily access the {@link https://developers.google.com/loader/ Google API loader}.
 *
 * @author Qiang Xue <qiang.xue@gmail.com>
 * @package system.web.helpers
 */
class CGoogleApi
{
    /**
     * @var string Protocol relative url to the Google API loader which allows easy access
     * to most of the Google AJAX APIs
     */
    public static $bootstrapUrl = '//www.google.com/jsapi';

    /**
     * Renders the jsapi script file.
     * @param string $apiKey the API key. Null if you do not have a key.
     * @return string the script tag that loads Google jsapi.
     */
    public static function init($apiKey = null)
    {
        if ($apiKey === null)
            return CHtml::scriptFile(self::$bootstrapUrl);
        else
            return CHtml::scriptFile(self::$bootstrapUrl . '?key=' . $apiKey);
    }

    /**
     * Loads the specified API module.
     * Note that you should call {@link init} first.
     * @param string $name the module name
     * @param string $version the module version
     * @param array $options additional js options that are to be passed to the load() function.
     * @return string the js code for loading the module. You can use {@link CHtml::script()}
     * to enclose it in a script tag.
     */
    public static function load($name, $version = '1', $options = array())
    {
        if (empty($options))
            return "google.load(\"{$name}\",\"{$version}\");";
        else
            return "google.load(\"{$name}\",\"{$version}\"," . CJavaScript::encode($options) . ");";
    }

    /**
     * Registers the specified API module.
     * This is similar to {@link load} except that it registers the loading code
     * with {@link CClientScript} instead of returning it.
     * This method also registers the jsapi script needed by the loading call.
     * @param string $name the module name
     * @param string $version the module version
     * @param array $options additional js options that are to be passed to the load() function.
     * @param string $apiKey the API key. Null if you do not have a key.
     */
    public static function register($name, $version = '1', $options = array(), $apiKey = null)
    {
        $cs = Yii::app()->getClientScript();
        $url = $apiKey === null ? self::$bootstrapUrl : self::$bootstrapUrl . '?key=' . $apiKey;
        $cs->registerScriptFile($url, CClientScript::POS_HEAD);

        $js = self::load($name, $version, $options);
        $cs->registerScript($name, $js, CClientScript::POS_HEAD);
    }
}